The present invention relates to a Universal Serial Bus (hereinafter USB) hub, and more particularly to a modular stackable component system including a base unit and one or more stackable USB hubs mounted to the base unit.
A personal computer system typically includes a computer, a display such as a CRT or flat panel display, and other peripheral devices communicating with the computer for entering data, printing data or controlling the computer. The peripheral devices require a connection to the computer which will enable them to communicate with the computer. Typically, most peripheral devices communicate with the computer over an individual connection cable having a corresponding connector attached to the computer.
A USB hub provides a convenient central data connection point for attaching multiple peripheral devices to a computer. The hub relays data from the computer to all enabled devices connected to the data hub, and relays data from the enabled devices to the computer. This data relay is performed without any data storage or significant delay. The USB hub is connected to the computer via a single USB upstream connector. The USB hub also includes a plurality of downstream ports for connecting the peripheral devices to the hub. The USB hub uses a standardized connectors at the upstream and downstream ports to provide universal connectivity between peripheral devices and the computer thus simplifying these connections by eliminating different cords and connectors.
Conventional USB hubs receive power for low power applications via a positive voltage conductor and a ground conductor from a source, such as the computer, through the upstream port. Conventional USB hubs are also equipped with a connector for connecting with a transformer plugged into a typical AC outlet for providing DC power to the hub for high power applications. When more than one USB hub is used, each hub is connected to a separate transformer for high power applications resulting in a clutter of cords, transformers, and used outlets. It is desirable to simplify the connection of multiple USB hubs thereby reducing the number of cords and transformers needed as well as providing a more space efficient footprint.